Fleur's name had always been top secret, and most of the Qing Eliminating Society didn't even know her gender. She used a voice changer when issuing direct orders, and Rachel herself only knew because her maternal grandmother happened to have personal connections to the Griffin branch in charge of the Left Military Governorate.
It was a tale as old as time—people talking in their sleep.
Still, that was how Rachel knew, and if not for that, she wouldn't even know who Charlie was talking about.